Read elements and write elements are located separately in a magnetic heads (e.g., magnetoresistive (MR) heads). Therefore, write head position during data writing requires a different offset than read head position during data reading, which is referred to as read/write offset (RWO) or micro-jog. In particular, RWO changes at different cylinder locations because the actuator motion is rotary and the skew angle of the head against the track direction is different at different tracks. For example, RWO is different at the inner diameter (ID) than the outside diameter (OD) of the magnetic disk. Moreover, temperature changes within a hard disk drive (HDD) can change RWO requirements due to, but not limited to, thermal expansion/contraction of track pitch and the magnetic head
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